Fair value option - Assets and Liabilities (Details) - Investment Management funds - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Assets of consolidated investment management funds:
Trading assets	$ 215	$ 229
Other assets	14	16
Total assets	229	245
Liabilities of consolidated investment management funds:
Other liabilities	1	1
Total liabilities	$ 1	$ 1

Assets of Consolidated Investment Management Funds [Abstract]

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- Definition

Liabilities of Consolidated Investment Management Funds [Abstract]

+ References

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Fair value of financial and nonfinancial obligations.

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- Definition

Fair value portion of other assets.

+ References

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- Definition

Fair value portion of other liabilities.

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.4)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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